Classifications

• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
  • H04R1/00—Details of transducers, loudspeakers or microphones
  • H04R1/10—Earpieces; Attachments therefor ; Earphones; Monophonic headphones
  • H04R1/1008—Earpieces of the supra-aural or circum-aural type
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
  • H04R1/00—Details of transducers, loudspeakers or microphones
  • H04R1/10—Earpieces; Attachments therefor ; Earphones; Monophonic headphones
  • H04R1/1058—Manufacture or assembly
  • H04R1/1075—Mountings of transducers in earphones or headphones
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
  • H04R1/00—Details of transducers, loudspeakers or microphones
  • H04R1/10—Earpieces; Attachments therefor ; Earphones; Monophonic headphones
  • H04R1/1083—Reduction of ambient noise

Definitions

• TITLE “An electroacoustic earcup for open-back headphones”
• the present disclosure relates to an electroacoustic earcup for headphones, as defined in the preamble of claim 1 and to open-back headphones as claimed in claim 10
• the electroacoustic earcup comprises a pair of electroacoustic transducers both in fluid communication with the outside environment, and is configured for use with phones of the open-back type.
• Electroacoustic earcups for open-back headphones are known to comprise a hollow housing having first and second openings in fluid communication with the outside environment.
• An air-permeable earpad is connected to the first opening and an air-permeable cover is connected to the second opening.
• An electroacoustic transducer is placed in the hollow housing and comprises a vibrating diaphragm to direct sound waves toward the ear of a listener.
• the vibrating diaphragm of the electroacoustic transducer can move within the hollow housing substantially as if it were in free air.
• the sounds from the environment and the sounds produced by the electroacoustic transducer can freely enter and exit the housing, for the listener to have a more natural perception of the reproduced sounds, similar to loudspeakers’ hearing experience.
• electroacoustic earcups having a single electroacoustic transducer for open-back headphones have a less than accurate sound response.
• the vibrating diaphragm will have too long acceleration and deceleration times to ensure high fidelity audio reproduction, possibly leading to an unpleasant listening experience.
• the invention has the object of providing an electroacoustic earcup for open- back headphones that can solve the problems of the above discussed prior art.
• Another object of the present invention is to provide open-back headphones comprising a pair of electroacoustic earcups.
• One embodiment can provide an electroacoustic earcup for open-back headphones that can improve sound reproduction as compared with known devices.
• One embodiment can provide an electroacoustic earcup for open-back headphones with a vibrating diaphragm having much shorter acceleration and deceleration times than prior art headphones having a single electroacoustic transducer.
• FIG. 1 shows an exploded view of the electroacoustic earcup
• FIG. 2 shows a schematic view of the assembled electroacoustic earcup
• FIG. 3 shows a schematic of the electrical connections of the electroacoustic ear cup
• FIG. 4 shows a perspective view of open-back headphones with a pair of electroacoustic earcups of Figure 2.
• numeral 2 designates the hollow housing 2 which acts as a support frame for the parts of the electroacoustic earcup 1.
• This hollow housing 2 extends in a main direction A between first and a second walls 3, 4 connected by a side wall 5.
• the first wall 3 has a first opening 30 and second wall 4 has a second opening 40.
• the first and second openings 30, 40 are transverse to the main direction A.
• the first and second openings 30, 40 extend throughout the respective walls 3, 4, are perpendicular to the main direction A, and have the same size.
• the hollow housing 2 is open in the direction of extension A and is delimited by the side wall 5. Therefore, the hollow housing 2 preferably has a cylindrical shape.
• the electroacoustic earcup 1 comprises an air-permeable earpad 6e whose shape mates with that of a human ear.
• Such earpad 6 is operably connected in fluid communication with the first opening 30 of the hollow housing 2. In operation, the earpad 6 rests on the ear of a listener and air freely flows from/to the hollow housing 2
• An air-permeable cover 7 is associated with the hollow housing 2. Such cover 7 is operably connected in fluid communication with the second opening 40 of the hollow housing 2. Thus, even with the cover, air freely flows from/to the hollow housing 2.
• the electroacoustic earcup 1 comprises a first electroacoustic transducer 8a and a second electroacoustic transducer 8b which are adapted to convert an input electrical signal into an output acoustic signal.
• the first and second electroacoustic transducers 8a, 8b are arranged within the hollow housing 2 one behind the other in the main direction A.
• the first electroacoustic transducer 8a is meant to be the transducer that is closer to the first opening 30 and the second electroacoustic transducer 8b is meant to be the transducer that is closer to the second opening 40.
• both electroacoustic transducers 8a, 8b comprise a vibrating diaphragm lOa, lOb that faces the first opening 30 of the hollow housing 2.
• both electroacoustic transducers 8a, 8b define an input surface 1 la. 1 lb that faces the second opening 40 of the hollow housing 2.
• Such input surface 11 a, l lb of each electroacoustic transducer 8a, 8b is in fluid communication with its respective vibrating diaphragm lOa, lOb.
• this diaphragm lOa, lOb oscillates, it moves an air mass in front and/or on the back of the diaphragm lOa, lOb in the main direction A, thereby reproducing sound waves that propagate from within the hollow housing 2 to the outside toward the first and second openings 30, 40.
• the first and second electroacoustic transducers 8a, 8b are hermetically connected by the side wall 5 of the hollow housing 2.
• the electroacoustic transducers 8a, 8b are peripherally connected to the side wall 5 in its surface that faces the hollow portion of the hollow housing 2. This connection peripherally seals each electroacoustic transducer 8a, 8b in the housing such that an isobaric chamber 12 will be defined between the two electroacoustic transducers 8a, 8b.
• This isobaric chamber 12 is delimited, in the direction A, between the diaphragm lOb of second electroacoustic transducer 8b and the input surface l la of the first electroacoustic transducer 8a and is laterally delimited by the side wall 5 of the hollow housing 2. Since the input surface l la is in fluid communication with its respective diaphragm lOa, said isobaric chamber 12 substantially encloses an air mass under constant pressure between the diaphragm lOb of second electroacoustic transducer 8b and the diaphragm lOa of the first electroacoustic transducer 8a.
• the electroacoustic transducers 8a, 8b are magneto-dynamic full-range transducers.
• the electroacoustic transducers 8a and 8b comprise:
• Each support base l6a, l6b extends between a support surface 24a, 24b and the input surface l la, l lb.
• Each support base l6a, l6b is arranged to be coaxial with the main direction A of the hollow housing 2 and preferably has a cylindrical shape.
• Each support base l6a, l6b comprises a conductive plate l7a, l7b, a centrally- positioned coil l8a, 18b and a plurality of radially-positioned vent holes 20a, 20b extending from the input surface l la, 1 lb to the support surface 24a, 24b.
• the support base l6a, l6b comprises an electric circuit that has two contact poles, a positive pole l90a, l90b and a negative pole l9la, l9lb.
• the vibrating diaphragm lOa, lOb is connected to the support surface 24a, 24b via the coil l8a, 18b.
• the plurality of permanent magnets 22a, 22b are radially positioned on the input surface 11 a, l lb.
• the covering body 2 la, 2 lb has a plurality of openings 25a, 25b and its shape mates that of the support base l6a, l6b to be coupled therewith and to protectively cover the diaphragm lOa, lOb.
• the fixing ring 23a, 23b is coupled to its respective support base l6a, l6b and connects it to the hollow housing 2 in the preferred position.
• first and second electroacoustic transducers 8a, 8b are coaxially arranged in the hollow housing 2.
• the first and second electroacoustic transducers 8a, 8b are electrically connected in series.
• the positive pole l90b of the second electroacoustic transducer 8b is electrically connected to the negative pole l9la of the first electroacoustic transducer 8a, and the current is delivered through electrical connections between an amplifier connected to the negative pole 19 lb of the second electroacoustic transducer 8b and to the positive pole l90a of first electroacoustic transducer 8a.
• An electrical input signal propagates in the coil l8a, 18b immersed in a permanent magnetic field, causes it to oscillate and, as a result causes the diaphragm lOa, lOb to vibrate and reproduce audio signals.
• the series connection of the two electroacoustic transducers 8a, 8b increases the power handling of the electroacoustic earcup 1 and limits the range of movement of the vibrating diaphragm lOa, lOb and, as a result, the possible distortions caused thereby.
• the coaxial arrangement of the two electroacoustic transducers 8a, 8b, separated along the main direction A from the isobaric chamber 12, improves control of the movement of the vibrating diaphragms lOa, lOb.
• the diaphragm lOa of the first electroacoustic transducer 8a is not only guided by the movement of its respective coil l8a, but also by the synchronous movement of the diaphragm lOb of the second electroacoustic transducer 8b which pushes the pressurized air mass in the isobaric chamber 12.
• the synchronous movement of the diaphragm lOb of the second electroacoustic transducer 8b facilitates air inflow and outflow through the openings 30, 40 of the hollow housing 2 caused by the diaphragm lOa of the first electroacoustic transducer 8a and vice versa, which will greatly reduce the acceleration and deceleration times of the diaphragms lOa, lOb.
• an increased magnetic flux may be triggered between the magnets 22a, 22b of the first and second electroacoustic transducers 8a, 8b, which will afford improved control of the movement of the respective vibrating diaphragms lOa, lOb.
• the distance between the vibrating diaphragm lOb of second electroacoustic transducer 8b and the input surface l la of the first electroacoustic transducer 8a ranges from 5 mm to 20 mm, and is more preferably 13 mm to maximize the magnetic flux triggered between the two electroacoustic transducers 8a, 8b.
• this distance is l2mm or l4mm.
• the distance between the two electroacoustic transducers 8a, 8b is meant to be the minimum distance between the diaphragm lOb and the input surface 1 la.
• the electroacoustic earcup 1 comprises a lining made of a sound-proof material 9 associated with the side wall 5 of the hollow housing 2 and with the cover 7, on the surface that faces the hollow portion.
• the lining made of sound-proof material 9 comprises a first layer 13 of a sound-insulating material and a second layer of a sound-absorbing material 14.
• the first layer of sound-insulating material 13 is adapted to damp the typical resonances and vibrations of typically selected materials.
• the surface of the side wall 5 that faces the hollow portion of the hollow housing 2 is covered by the first layer of sound-insulating material 13 in the portion of the isobaric chamber 12. More preferably, the material of the first sound-insulating layer is a Dynamat Xtreme mat.
• the second layer of sound-absorbing material 14 is adapted to dampen the reflections of the acoustic waves in the hollow housing 2, hence also in the isobaric chamber 12.
• the material of the second sound-absorbing layer 14 is a felt.
• the earpad 6 is formed with an open-cell porous material that, when in resting upon an ear, allows the air to reversibly flow between the interior of the hollow housing 2 and the outside environment.
• the selected porous material has an pore-per-inch index, PPI ranging from 10 to 90 pores per inch, equivalent to a pore-per-millimeter value ranging from 0.4 to 3.6 pores per millimeter. More preferably the selected porous material has a PPI of 30 pores per inch, equivalent to 1.2 pores per millimeter.
• the selected porous material is an open-cell polyurethane.
• the earpad 6 comprises a central opening 15 at the first opening 30 of the hollow housing 2 with which it is operably connected.
• the diaphragm lOa of the first electroacoustic transducer 8a is capable of unimpeded emission of acoustic waves toward the ear of the user.
• the earpad 6 may be of circumaural type, i.e. completely encircling the ear of the user, or of supra-aural type, i.e. resting on the ear of the user.
• the air-permeable cover 7 that is coupled with the hollow housing 2 has a plurality of vent holes 26 at the second opening 40 with which it is operably connected.
• the hollow housing 2 and the cover 7 are made of aluminum.
• the present invention provides open-back headphones 100 comprising a pair of electroacoustic earcups la, lb as described hereinabove.
• the headphones include a flexible headband 101 extending between a first end lOla and a second end 10 lb and formed to rest upon the head of a user.
• a first electroacoustic earcup la and a second electroacoustic earcup lb are connected to the ends lOla, 10 lb of the flexible headband 101.
• first and the second ends lOla, lOlb of the headband 102 are connected to the first and second electroacoustic earcups la, lb respectively via first and second adjustment members l02a, l02b for adjusting the position of each electroacoustic earcup la, lb as needed by the user.
• the adjustment members l02a, l02b can substantially adjust the positions of the electroacoustic earcups la, lb between an extended position and a retracted position, i.e. can substantially adjust the length of the flexible headband 101
• each adjustment member l02a, l02b has a box shape extending between a top wall 103 a, l03b and a bottom wall l04a, l04b and has a through hole extending between the bottom wall l04a, l04b and the top wall 103 a, l03b.
• each adjustment member l02a, l02b is unremovably connected to its respective end lOla, 10 lb of the headband 101.
• An adjustment rod l06a, l06b extends in the through hole of each adjustment member l02a, l02b between a lower end l07a, l07b and an upper end l08b, l08a.
• the lower end l07a, l07b of each adjustment rod l06a, l06b is unremovably connected to its respective electroacoustic earcup la, lb.
• each adjustment member l02a, l02b can slide on its respective adjustment rod l06a, l06b between an extended position and a retracted position.
• the upper end l08b, l08a of the adjustment rod l06a, l06b is held within the adjustment member l02a, l02b.
• the upper end l08b, l08a of the adjustment rod l06a, l06b is spaced apart from the upper wall 103 a, l03b of its respective adjustment member l02a, l02b and its respective earcup la, lb rests on the bottom surface l04a, l04b of its respective adjustment member l02a, l02b.
• the headphones 100 comprise an electrical connection cable 109 having first and second terminal parts 110, 111.
• the first terminal part 110 is connected to an electrical connection element 112 adapted to be connected to an amplifier (not shown).
• the second terminal part 111 is connected to first and second cables 11 la, 11 lb, respectively connected to the electric circuit of the first and second acoustic earcups la, lb.

Landscapes

• Engineering & Computer Science (AREA)
• Physics & Mathematics (AREA)
• Acoustics & Sound (AREA)
• Signal Processing (AREA)
• Manufacturing & Machinery (AREA)
• Headphones And Earphones (AREA)
• Adornments (AREA)

Priority Applications (1)

Applications Claiming Priority (2)

Publications (2)

Family

ID=63014891

Family Applications (1)

Country Status (8)

Families Citing this family (1)

Family Cites Families (10)

• 2018
  • 2018-05-04 IT IT102018000005087A patent/IT201800005087A1/it unknown
• 2019
  • 2019-05-03 CN CN201980043673.6A patent/CN112470488B/zh active Active
  • 2019-05-03 RS RS20220988A patent/RS63732B1/sr unknown
  • 2019-05-03 DK DK19726161.3T patent/DK3788795T3/da active
  • 2019-05-03 PL PL19726161.3T patent/PL3788795T3/pl unknown
  • 2019-05-03 WO PCT/IB2019/053622 patent/WO2019211801A1/en active Application Filing
  • 2019-05-03 EP EP19726161.3A patent/EP3788795B1/de active Active
  • 2019-05-03 US US17/053,031 patent/US20210235182A1/en active Pending

Also Published As

Similar Documents

Legal Events